Channeling Radiation in a Crystal Undergoing an Action of Ultrasonic or Electromagnetic Waves

The radiation emitted by channeled electrons and positrons in a crystal undergoing an action of ultrasonic (electromagnetic) waves is considered in quantum approximation. The most general crystal potential is shown to consist of two terms: the stationary and nonstationary ones both depending on the atomic displacements caused by the wave. As a result the peak positions and intensities of channeling radiation depend on the wave intensity, too. At resonance between one of the perturbation harmonics of the crystal potential and the proper particle transition the calculated radiation rate exceeds that one without wave by several orders.